create-custom-meta-box-in-post-edit-screen.php

<?php
/* Create custom meta data box to the post edit screen */

function jpen_custom_post_sort( $post ){
  add_meta_box( 
    'custom_post_sort_box', 
    'Position in List of Posts', 
    'jpen_custom_post_order', 
    'post' ,
    'side'
    );
}
add_action( 'add_meta_boxes', 'jpen_custom_post_sort' );
?>